dSPACE DS1103 Control Workstation Tutorial and DC

Motor Speed Control

Project Report

By

Annemarie Thomas

Advisor: Dr. Winfred Anakwa

May 12, 2009

Abstract

The dSPACE DS1103 software and hardware tools for embedded system development come

with several volumes of documentation. Consequently, the user must spend a lot of time

learning how to use the tools. The purpose of this project is to write a tutorial using DC motor

speed control as the example application in order to decrease the time required by future students

to learn how to use the workstation so they may complete more complex projects. This required

a detailed study of the DS1103 hardware and software tools, design of a controller for the DC

motor and simulation of the controller in Simulink. RealTime Workshop and ControlDesk were

used to generate C code for the digital controller equation automatically and download it to the

DS1103 board for execution. ControlDesk software was then used to monitor and control a

variety of variables.

Table of Contents

Introduction .............................................................................................................. 1

Project Summary ..................................................................................................... 1

Functional Description ............................................................................................ 1

ControlDesk/Speed Input ............................................................................................................ 2

CLP1103 ..................................................................................................................................... 2

Motor Subsystem ......................................................................................................................... 2

Optical Encoder Subsystem ........................................................................................................ 3

Requirements ............................................................................................................ 3

Overall System Requirements ..................................................................................................... 3

Controller Requirements ............................................................................................................. 4

Other Requirements .................................................................................................................... 4

Equipment ................................................................................................................. 5

Workstation ................................................................................................................................. 5

Other Equipment ......................................................................................................................... 5

Project Implementation ........................................................................................... 6

Plant Model ................................................................................................................................. 6

Controller Design ....................................................................................................................... 7

MATLAB Calculations ................................................................................................................ 8

Simulink Simulation .................................................................................................................. 10

Actual System ............................................................................................................................ 13

Conclusions .............................................................................................................18

References ...............................................................................................................19

Appendix A: MATLAB Code and Results ......................................................... A1

MATLAB Code .......................................................................................................................... A1

MATLAB Results ....................................................................................................................... A3

Appendix B: Project Completion Timeline ........................................................ B1

Appendix C: Datasheet Excerpts ......................................................................... C1

Transistor .................................................................................................................................. C1

Inverter ...................................................................................................................................... C2

Encoder ..................................................................................................................................... C6

Thomas 1

Introduction

The dSPACE DS1102 was first used at Bradley University in the year 2000 when a user‟s

manual and a workstation based on this board were developed. Since then, a newer dSPACE

DS1103 board has become available. With grant from the Bradley College of Engineering of

$2,000 and additional funds of $12,200 provided by Dr. Larry Kendrick and Mr. Shawn Weck at

the Caterpillar Technical Center, a dSPACE DS1103 board and additional equipment required

have been purchased to set up a DS1103 workstation. Initial setup has been completed by Mr.

Chris Mattus. The object of the dSPACE DS1103 Control Workstation Tutorial and DC Motor

Speed Control project is to develop a tutorial for use of the new dSPACE DS1103 Workstation

by implementing a DC motor speed control system. The tutorial will minimize the time required

for future students to become proficient in using the workstation, therefore increasing the time

they can spend designing and implementing more complex control systems.

Project Summary

The goals of the dSPACE DS1103 Control Workstation Tutorial and DC Motor Speed Control

project are the following:

Determine and implement any additional setup that may be required for the dSPACE

DS1103 control workstation.

Write a tutorial for use of the workstation, paying particular attention to details

related to the DS1103 board using a DC motor speed controller as the example

application.

Design a controller to control the speed of a DC motor.

Implement the designed DC motor speed controller on the dSPACE DS1103 system

using the Simulink and the dSPACE blocksets, the Matlab-to-DSP interface libraries,

Real-Time Interface to Simulink, and Real-Time Workshop.

Functional Description

The design portion of this project involves designing and implementing a motor speed controller

using the dSPACE DS1103 board. The controller was designed and simulated using the

Simulink and the dSPACE blocksets, the Matlab-to-DSP interface libraries, Real-Time Interface

to Simulink, and Real-Time Workshop on a PC. The controller was then downloaded onto the

Texas Instruments‟ TM320F240 DSP [1] located on the DS1103 board. Inputs to the DS1103

include the desired motor speed and the output of the optical encoder connected to the motor.

Outputs from the DS1103 include the PWM signal input to the motor and the display of the

actual motor speed. Inputs to and outputs from the DS1103 pass through the CLP1103 [2]

connector panel for the DS1103 board or through the cables connected to the computer. The

motor‟s speed remains reasonably steady until a certain amount of load torque is applied to it by

a brake. A general block diagram for the system is shown in figure 1 on the next page.

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DS1103

Motor System

ControlDesk

(Desired Speed

Input)

Load Applied to

Motor Shaft

By Brake

Optical Encoder

CLP1103

Connector

Panel

Figure 1: Motor Speed Control System Block Diagram

ControlDesk/Speed Input

“ControlDesk” in figure 1 serves multiple uses. It provides the interface for downloading

controller models designed in Simulink onto the DSP. The Instrument Panel feature of

ControlDesk is used to display various measurements such as the duty cycle of the PWM signal

entering the motor and the actual velocity in RPM that the motor is running at and is used to

control inputs such as the “Desired Speed Input” to the controller. Some inputs, such as the

signal from the “Optical Encoder Subsystem”, must be sent through the “CLP1103” and

“DS1103” before the measurements can be displayed in ControlDesk on the computer [3].

Initially, measurement of the system response (the actual motor speed) was completed by

connecting the output of the Optical Encoder to an oscilloscope in order to verify the behavior of

the outputs of the encoder blocks provided with the DS1103 software for Simulink and the

results observed the ControlDesk layout.

CLP1103

The “CLP1103” shown in figure 1 serves as an interface between the “DS1103” and the external

hardware portion (“Motor System”, “Optical Encoder) of the overall system. The CLP1103

contains connectors for twenty (20) Analog-to-Digital inputs, eight (8) Digital-to-Analog

outputs, several other connectors that can be used for Digital I/O, Slave/DSP I/O, Incremental

Encoder Interfaces, CAN interface, and Serial Interfaces [2]. This project uses the Slave I/O

Connector to output the PWM signal from the DS1103 to the Motor Subsystem and an

Incremental Encoder connector to pass the Optical Encoder output to the DS1103.

Motor Subsystem

The “Motor System” identified in the block diagram in figure 1 includes the motor and

additional analog components. Further information about the Motor Subsystem can be found in

the Equipment section under Other Equipment section.

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Optical Encoder Subsystem

The “Optical Encoder System” shown in figure 1 simply consists on the optical encoder

connected to the motor and the necessary (2.7 kΩ) pull-up resistors (connected between Channel

A and 5 Volts and Channel B and 5 Volts) and power/ground connections with no additional

analog components being needed to convert the optical encoder output signal into a form that can

be more easily handled by the DSP.

Requirements

The requirements for this project are currently as follows:

Overall System Requirements

Requirements and specifications for the overall system shown in figure 1 on page 2 are as

follows:

The operating range of the system shall be 0 to 40 degrees C.

The system shall use a 30 VDC or smaller power supply. (Uses 24 VDC Supply.)

The motor used shall be a Pittman DC Motor Model Part # GM9236C534-R2.

The values for the motor model to be used for design and simulation in Simulink shall be

determined from the datasheets and verified experimentally.

A control panel shall be created in the “ControlDesk” application to monitor the inputs

and the outputs of the system.

The output from the “DS1103” to the “Motor System” shall be passed through a PWM

output located on the “CLP1103 Connector Panel”.

The output from the “DS1103” to the “Motor System” shall be a 12 kHz PWM signal.

The input to the “DS1103” from the “Optical Encoder System” shall be passed through

an Incremental Encoder input located on the “CLP1103 Connector Panel”.

The input to the “DS1103” from the “Optical Encoder System” shall be converted to

RPM for display purposes.

The RPM measurement displayed using a control panel in “ControlDesk” shall be within

±10 RPM of the actual value. (This requirement has not been met. It would require an

encoder with higher resolution.)

There shall be a method to input/control the desired speed of the motor.

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The desired maximum speed/velocity that shall be input is 660.594 RPM.

Load Torque shall be applied to the motor shaft using a HB-420 Brake.

Note: The maximum load torque that can be applied has been limited to reasonable

values.

The designed controller shall be downloaded onto the Texas Instruments‟ TM320F240

DSP [1] located on the “DS1103” board using “ControlDesk”.

Controller Requirements

Requirements and specification applicable to the controller functionality are as follows:

The DC motor speed controller shall be designed/simulated using Simulink and dSPACE

blocksets, Matlab-to-DSP interface libraries, the Real-Time Interface to Simulink, and

Real-Time Workshop.

Overshoot shall be less than or equal to 5%.

Rise time shall be less than or equal to 110 ms.

Steady-state error shall be minimized.

Other Requirements

Other requirements particular to this project are as follows:

A tutorial shall be written on the use of the workstation using the DC motor speed

controller as the example application.

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Equipment

Equipment used in this project is as follows:

Workstation

The dSPACE DS1103 control workstation contains the following:

The $14,000 dSPACE DS1103 system consisting of:

o A DS1103 Board.

o An Expansion Box to house the DS1103.

o A CLP1103 PPC Connector and LED Panel.

o ControlDesk Version 3.2.2 and several other software applications provided

by dSPACE.

A PC dedicated to the workstation containing all software applications required for

controller design (Matlab/Simulink Version R2008a and libraries) and

implementation in the DS1103 (ControlDesk).

Other Equipment

Equipment particular to this project includes:

A Pittman GM9236C534-R2 DC Motor.

A Magtrol HB-420 Brake.

A TIP120 Transistor.

A IN4004 Diode.

SN7407 Hex Inverters.

Other electronic components, power supplies, and measurement devices.

A circuit for the Motor Subsystem is shown in figure 2 below.

Figure 2: Motor Subsystem

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Project Implementation

Plant Model

A simple motor model is shown in figure 3 below. From this model, an open loop control block

diagram can be generated with a transfer function for the input voltage to the motor, Va, in

relation to the output, w, in radians per second, which can then be easily be converted to other

formats such as RPM (revolutions per minute). A simple transfer function that can be used to

model the motor in the frequency domain, in terms of s, is:

Kv*KtJ*sBLasRa

Kt

Va

w

(1)

where Ra and La are the electrical resistance and inductance of the motor, J and B are the

mechanical inertia and damping/friction of the motor, and Kt and Kv are the torque constant and

back emf constant of the motor.

w

B

RaLa

Va J

Figure 3: Simple Motor Model Schematic

One of the requirements states, “The values for the motor model to be used for design and

simulation in Simulink shall be determined from the datasheets and verified experimentally.”

Unfortunately, there was not enough time to verify the motor model provided through

experimental measurements. The motor model used was generated in a previous project

completed by Amulya Sabbisetti [6]. Though not perfect, it was found that when comparing the

step response of the Simulink model for the entire system with no “BrakeTorque” applied to the

step response of the actual system as recorded using ControlDesk that the rise times of the actual

system and the simulation were fairly similar. These results are discussed in more depth in later

sections. The plant model used is shown in figure 4 below, and a plot of its frequency response

is shown in figure 5 on the next page showing its original phase margin of 84° at an ωc of 279

radians per second. The analog transfer function for this model is found in the equation that

follows:

GP =

11776.78

s1

14.54

s

19.4699

1776.78s14.54s

502852 (2)

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Figure 4: Motor Model

Figure 5: Frequency Response of the Motor Model.

Controller Design

The original rise time requirement was 20 ms. The controller was designed in the analog domain

using Bode method for this rise time and then converted to the digital domain using MATLAB.

First an integrator (GC = 1/s) was added to the controller to minimize the steady state error in the

system. It was determined that, for a rise time of 20 ms and overshoot of approximately five

percent (5%), an ωc of 157.08 radians per second with a phase margin of about 69.01° should be

the design specifications. This leads to the following calculations:

βc = -180°-69.01° = -110.99° = -1.937 radians (3)

-100

-50

0

50

Magnitu

de (

dB

)

10-1

100

101

102

103

104

105

-180

-135

-90

-45

0

Phase (

deg)

Bode Diagram

Gm = Inf dB (at Inf rad/sec) , Pm = 84 deg (at 279 rad/sec)

Frequency (rad/sec)

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βc 2

ω

cω

cω

1ω

2

π2

2

π

(4)

2ω

2cω

1ω

2ω1

ωcω (5)

Substituting in a βc of -1.937 radians, ωc = 157.08 radians per second, and equation 5 into

equation 4 leads to ω2 = 857.579 radians per second to be used as a pole of GC. Substituting this

ω2 into equation 5 leads to ω1 = 28.7718 radians per second to be used as a zero of GC. Adding

this pole and zero to GC provides and analog controller of:

GC

857.579ss

28.7718s

(6)

Adding gain and converting the analog controller using pre-warping and bilinear transformation

for a sampling frequency of 12 kHz (the required PWM frequency) generates a digital controller

as follows:

GCdigital =

0.9311.931z2z

0.99760.0024z2z

482282)72.0631(0.

0.931z1z

0.9976z1z482282)72.0631(0.

(7)

This equation was then implemented using MATLAB calculations and a Simulink simulation

and the gain was then adjusted to obtain the desired results.

MATLAB Calculations

The code and results for the MATLAB calculations and plots that were made are shown in

“Appendix A”. The gain of the system was adjusted from equation 7 above to adjust ωc to be

about 157 radians per second with a phase margin of about 69.5°. See figure 6 on the next page.

After the plant was converted from the analog to the digital domain using the „zoh‟

transformation in MATLAB, the digital controller was added, and the optical encoder gain was

added. The step response simulated in MATLAB is shown in figure 7 on the next page. The

step response shows about six percent (6%) overshoot and a rise time of approximately 8.33 ms

([125-25samples]*[1/12000] seconds per sample).

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Figure 6: Frequency Response for combined digital controller and digital plant plotted in MATLAB.

Figure 7: Step response generated by MATLAB code.

0 200 400 600 800 1000 1200 1400 1600 1800 20000

0.2

0.4

0.6

0.8

1

1.2

1.4

System: sys

Time (sec): 165

Amplitude: 1

System: sys

Time (sec): 249

Amplitude: 1.06

System: sys

Time (sec): 125

Amplitude: 0.901

System: sys

Time (sec): 25

Amplitude: 0.104

Step Response

Samples (sec)

Am

plit

ude

-150

-100

-50

0

50

Magnitu

de (

dB

)

100

101

102

103

104

105

-270

-225

-180

-135

-90

Phase (

deg)

Bode Diagram

Gm = 24.2 dB (at 1.22e+003 rad/sec) , Pm = 69.5 deg (at 157 rad/sec)

Frequency (rad/sec)

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Simulink Simulation

The controller designed in MATLAB was then added to the Simulink simulation model and the

closed loop system exhibited no overshoot and a significantly longer rise time. Similar rise time

results were found when data was recorded with the controller downloaded to the DS1103 but

overshoot or lack thereof was hard to detect using the data recorded by ControlDesk. Additional

gain was added to the Simulink simulation, which was then also added to the controller

downloaded to the DS1103, to obtain about five percent (5%) overshoot and a rise time of about

110 ms. The blocks used in the Simulink simulation are shown in figures 8-13 that follow. The

Controller subsystem is shown in figure 10 on the next page. The “Hz_DutyCycle” gain block in

figure 8 below is needed to convert the output of the “Controller”, which is a frequency value, to

a duty cycle value that can then be converted to the voltage input for the “Motor” subsystem

using the “PWM_to_Volts” subsystem, which models the effects of the hardware between the

PWM output and the motor in the actual system.

Figure 8: Simulink Model used to verify controller functionality.

Figure 9: Motor Subsystem for Simulink model in figure 8 above.

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Figure 10: Controller Subsystem for Simulink model in figure 8 one the previous page.

Figure 11: RPM_to_Pulses Subsystem for Simulink model in figure 8 on the previous page.

Figure 12: Pulses_to_RPM Subsystem for Simulink model in figure 8 on the previous page.

Figure 13: PWM_to_Volts Subsystem used to model the effects of the PWM and hardware connected to the motor for Simulink model in figure 8 on the previous page.

The approximate step response for the Simulink simulation was obtained for an RPM_in of

238.57 revolutions per minute in order to compare it to the MATLAB results which corresponds

to the desired Pulses into the summer block from both the input and the bottom portion of the

controller loop. RPM_in of 239.57 revolutions per minute is approximately equal to one Pulse.

The step response for the simulation is shown in figure 14 below with measurements shown to

obtain five percent (5%) overshoot and approximately 110 ms rise time calculations:

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

0.2

0.4

0.6

0.8

1

1.2

1.4

X: 0.2237

Y: 1.05X: 0.1608

Y: 1.001

X: 0.1242

Y: 0.9009

X: 0.01342

Y: 0.1003

Figure 14: Step response for Simulink simulation. .

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The possible effects of the “BrakeTorque” input shown in figure 8 on page 11 were also

observed for RPM_in of 200 revolutions per minute. The results are shown in figures 15-17 that

follow. For lower “BrakeTorque”, there is a level at which RPM_out does not go directly to 200

revolutions per minute, but spikes at a lower value before dropping and then rising up to the

desired level. Eventually, for higher levels of “BrakeTorque”, the desired speed is not reached

until enough torque is applied and the output only spikes and the motor stops completely. The

torque values do not correspond to those that affect the actual system and the initial spikes

almost never if ever seen. The transitions in the actual system are generally fairly smooth.

0 1 2 3 4 5 6 70

50

100

150

Figure 15: RPM_out when RPM_in = 200 RPM and BrakeTorque = 0.15N-m for the Simulink Model shown in Figure 4

0 1 2 3 4 5 6 70

20

40

60

80

100

120

140

160

180

200

Figure 16: RPM_out when RPM_in = 200 RPM and BrakeTorque = 0.1N-m for the Simulink Model shown in Figure 8

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0 1 2 3 4 5 6 70

50

100

150

Figure 17: RPM_out when RPM_in = 200 RPM and BrakeTorque = 0.2N-m for the Simulink Model shown in Figure 8

Actual System

The Simulink model downloaded to the DS1003 board is very similar to the Simulink simulation

in the previous section, but there are some differences. Of particular importance are the

dSPACE provided blocks for outputting the PWM to the Motor System and inputting the

encoder output to the model through the CLP1103 Connector Panel. For more information about

how the actual system was implemented, see the “Motor Speed Control Application” section of

the tutorial written as a part of this project [4]. The Simulink model downloaded to the DS1103

board is shown in figures 18-19 below.

Figure 18: Simulink model downloaded to the DS1103.

Figure 19: Controller subsystem shown in figure 18 above.

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When the controller from the Simulink simulation, which is shown in figure 10 on page 12, was

added to the Simulink model, a very similar rise time was observed in the data recorded in

ControlDesk for a unit step input, but no overshoot seemed to exist. These results are shown in

figures 20-22 below.

0 0.5 1 1.5 2 2.5 3 3.5 40

50

100

150

200

250

X: 2.141

Y: 0

X: 2.422

Y: 0

X: 3.424

Y: 178.9

X: 3.636

Y: 238.6

X: 2.53

Y: 200

Figure 20: RPM_in and RPM_out for 200RPM input recorded using ControlDesk and plotted using MATLAB.

0 0.5 1 1.5 2 2.5 3 3.5 40

50

100

150

200

250

Figure 21: Simulink simulation results when RPM_in of 200RPM is applied at 2.14 s similar to figure 20 above are plotted in MATLAB.

Thomas 15

0 0.5 1 1.5 2 2.5 3 3.5 40

50

100

150

200

250

Figure 22: MATLAB plot of RPM_out from figures 20-21 on the previous page.

Figure 22 above shows that the rise times for the Simulink simulation and the actual system are

very similar, but it appears there may be some time delay in the actual system. The

measurements taken in figure 20 on the previous page from the actual system show a rise time of

less than 108 ms and no visible overshoot. This plot does not prove there is no overshoot in the

actual system since the error that cannot be entirely removed in the system due to various types

of rounding causes the output to alternate between a value above and a value below the desired

speed in an aperiodic fashion that could hide overshoot. A frequency-to-voltage converter circuit

was attached to the encoder output and the oscilloscope to see if any overshoot could be

observed. The results are shown in figure 23 below.

Figure 23: Frequency-to-voltage converter output for a 200 RPM input.

Thomas 16

There is still not any overshoot visible. All plots up until this point have had no brake torque

applied. Attempts were made to take additional measurements using the frequency-to-voltage

converter for several input speeds and voltages applied to the brake. Taking measurements from

these plots was still difficult and uncertain. Estimations of rise time measurements from these

plots had slower rise times than desired. No overshoot was visible at lower input speeds, and it

was only slightly visible, probably in the three to four percent (3-4%) range for higher

frequencies when the torque of the brake was near the maximum the system could handle before

actually stopping. Additional measurements were also taken at various points in the hardware

system for a 238.57 RPM input which is approximately equal to a step input. The results are

shown in figures 24-25 below.

Figure 24: Collector Voltage, Motor Voltage, Motor Current, and Diode Current for a 238.57 RPM input.

Figure 25: PWM, Encoder output, Motor Current, and Diode Current for a 238.57 RPM input.

From the plots in figures 24-25 above, it is shown that when the PWM is on, the motor current

increases, the diode current is zero and the collector voltage of the transistor is small. When the

PWM is off, the decreasing motor current flows through the diode.

Thomas 17

The approximate maximum torque the system could handle was found to occur when somewhere

between 10.5-11+ Volts was applied to the brake. Generally the system would not start up again

until the voltage input to the brake dropped below about 8 Volts. These values correspond to

about 0.375 Nm or 50 OzIn of torque being applied by the brake. These values are shown in

figure 26 below. These two voltage values are different due to the hysteresis caused by the

structure and components of the brake.

Figure 26: Plot of Torque vs. Current/Voltage response of the brake with approximate cutoff toque/voltage of the brake plotted.

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Additional measurements were taken from the output of the frequency to voltage converter

circuit and a Pioneer Digital Photo Tach DT-36M. Some of these measurements are shown in

table 1 below.

Desired Speed (RPM)

Brake Voltage (V)

Actual Speed Range (RPM)

Speed Error (RPM)

Percent Overshoot (%)

Rise Time (ms)

238.57 0.00 238-239 ±0.5 0 160

7.12 216-225 -22.5 0 216

10.64 238-239 ±0.5 0 200

400 0.00 397-400 -3 0 195

7.19 391-400 -7/+4 0 195

10.60 398-401 -2/+1 3.20 344

600 0.00 598-602 ±2 0 120

7.15 568 -12 0 171

10.47 414-416 -186 4 325

Table 1: Measurements taken from frequency-to-voltage converter output and Digital Photo Tach.

Rise times recorded in table 1 above are longer than the desired specifications. It is possible the

system does not meet the specification for 110 ms rise time, but it might also be an issue related

to the frequency-to-voltage converter circuit, since the measurements generated from the data

recorded using ConrolDesk shows the response for a 200 RPM input is well within

specifications. The output of the frequency-to voltage converter was also not very smooth which

made taking measurements difficult for table 1 above. If there was any overshoot with lower

voltages applied to the brake, it was impossible to see. Even the overshoots that were seen at

near cutoff brake values were hard to detect and are approximations, but they do show that even

for the higher speed inputs, the specification for less that five percent (5%) overshoot seems to

still be met.

Conclusions

The goal of this project was to design and simulate a motor speed controller using MATLAB and

Simulink and then implement the controller on the DS1103 board using the dSPACE software.

Use of the dSPACE DS1103 workstation to perform this work was also to be documented in the

form of a tutorial, and this has been completed as well. The controller requirements were relaxed

when discrepancies were found between that MATLAB results and the actual system/Simulink

simulation. It is still uncertain as to whether the rise time and overshoot specifications are met or

not. Writing the tutorial [4] is the most important focus of this project due to its possible aide to

future students in designing and implementing more complex projects such as magnetic

levitation systems using the DS1103 workstation. It will allow them to spend significantly less

time learning how to use the workstation which will provide them with more time for design and

testing their system or learning about some of its higher-level abilities.

Thomas 19

References

[1] “DS1103 PPC Controller Board”, Germany: dSPACE, July 2008.

[2] “Connector and LED Panels,” Catalog 2008, Germany: dSPACE GmbH, 2008, p. 302.

[3] ControlDesk Experiment Guide For ControlDesk 3.2, Germany: dSPACE GmbH, 2008,

Release 6.1.

[4] Annemarie Thomas. "dSPACE DS1103 Control Workstation Tutorial and DC Motor Speed

Control: Tutorial", Senior Project Report, Bradley University ECE Department, May 2009.

[5] dSPACE System First Work Steps For DS1103, DS1104, DS1005, DS1006, and Micro Auto

Box, Germany: dSPACE GmbH, 2007, Release 6.0.

[6] Real-Time Interface (RTI and RTI-MP) Implementation Guide, Germany: dSPACE GmbH,

2008, Release 6.1.

[7] Sabbisetti, Amulya Sabbisetti. "Discrete Time Gain Scheduled Adaptive Control of DC

Motor Speed", Masters Project Report, Bradley University ECE Department, December 2008.

[8] DS1103 PPC Controller Board Hardware Installation and Configuration, Germany:

dSPACE GmbH, 2007, Release 6.0.

Thomas A1

Appendix A: MATLAB Code and Results

MATLAB Code

display(' ') display('**********START SIMULATION**********') ts=1/12000;%Sampling Time = 1/12kHz wc=157.08;%wc being designed for

%Analog Plant Transfer Function display('******Plant*******') gpanum=[502853];gpaden=[1 1791.32 25827.1]; gpa=tf(gpanum,gpaden)

%Digital Plant Transfer Function with prewarping at wc [gpdnum,gpdden]=c2dm(gpanum,gpaden,ts,'zoh'); gpd=tf(gpdnum,gpdden,ts)%Digital Transfer Function for plant zpk(gpd)%Factored Digital Transfer Function for plant

figure(1),rlocus(gpdnum,gpdden),title('Digital Plant Root Locus') figure(2),axis('square'),zgrid('new'),rlocus(gpdnum,gpdden),title('Digital

Plant Root Locus with Damping Ratio Lines')

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%This Section may NOT always be necessary and may need to be commented

out.%%%%%

%Analog Controller Transfer Function display('******Controller******') gcanum=[1 28.7718];gcaden=[1 857.578 0]; gca=tf(gcanum,gcaden)

%Digital Controller Transfer Function for Analog Controller with prewarping

at wc [gcdnum,gcdden]=c2dm(gcanum,gcaden,ts,'prewarp',wc); gcd=tf(gcdnum,gcdden,ts)%Digital Transfer Function for controller zpk(gcd)%Factored Digital Transfer Function for controller

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%Open Loop Combined Plant,Controller, and Optical Encoder Gain display('******Open Loop Response******')

ka=72.0631;%Controller Analog gain - Slight Change in gain should not make a

difference. kd=0.482282/0.000040278;%Controller Digital gain - MUST BE adjusted for

digital gain included in section above? koe=81.48;%Optical Encoder gain

k2=koe*ka*kd*.000006825;%Remove last gain term later.******************

Thomas A2

gpdnum2=gpdnum*k2;%Add complete Open Loop Gain [gpcnum,gpcden]=series(gpdnum2,gpdden,gcdnum,gcdden); gpc=tf(gpcnum,gpcden,ts) zpk(gpc)

figure(3),rlocus(gpcnum,gpcden),title('Open Loop Root Locus') figure(4),axis('square'),zgrid('new'),rlocus(gpcnum,gpcden),title('Open Loop

Root Locus with Damping Ratio Lines')

w=0.1:0.1:2000; [mag,phase,w]=dbode(gpcnum,gpcden,ts,w);

figure(5),margin(mag,phase,w)

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%Closed Loop Response display('******Closed Loop Response******')

[clnum,clden]=feedback(gpcnum,gpcden,1,1); cltf=tf(clnum,clden,ts) zpk(cltf)

figure(6),dstep(clnum,clden,1000),xlabel('Samples')

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

display('**********END SIMULATION**********')

Thomas A3

MATLAB Results

**********START SIMULATION**********

******Plant*******

Transfer function:

502853

------------------------

s^2 + 1791 s + 2.583e004

Transfer function:

0.001662 z + 0.001582

----------------------

z^2 - 1.861 z + 0.8613

Sampling time: 8.3333e-005

Zero/pole/gain:

0.0016623 (z+0.9515)

---------------------

(z-0.9988) (z-0.8624)

Sampling time: 8.3333e-005

-6 -5 -4 -3 -2 -1 0 1 2-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

Digital Plant Root Locus

Real Axis

Imagin

ary

Axis

Thomas A4

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

0.1/T

0.2/T

0.3/T

0.4/T0.5/T0.6/T

0.7/T

0.8/T

0.9/T

/T

0.1/T

0.2/T

0.3/T

0.4/T0.5/T

0.6/T

0.7/T

0.8/T

0.9/T

/T

0.1

0.2

0.30.40.50.60.70.8

0.9

Digital Plant Root Locus w ith Damping Ratio Lines

Real Axis

Imagin

ary

Axis

******Controller******

Transfer function:

s + 28.77

-------------

s^2 + 857.6 s

Transfer function:

4.028e-005 z^2 + 9.646e-008 z - 4.018e-005

------------------------------------------

z^2 - 1.931 z + 0.931

Sampling time: 8.3333e-005

Zero/pole/gain:

4.0278e-005 (z+1) (z-0.9976)

----------------------------

(z-1) (z-0.931)

Sampling time: 8.3333e-005

Thomas A5

******Open Loop Response******

Transfer function:

3.213e-005 z^3 + 3.064e-005 z^2 - 3.198e-005 z - 3.049e-005

-----------------------------------------------------------

z^4 - 3.792 z^3 + 5.386 z^2 - 3.396 z + 0.8019

Sampling time: 8.3333e-005

Zero/pole/gain:

3.2127e-005 (z-0.9976) (z+1) (z+0.9515)

---------------------------------------

(z-1) (z-0.9988) (z-0.931) (z-0.8624)

Sampling time: 8.3333e-005

-10 -8 -6 -4 -2 0 2-4

-3

-2

-1

0

1

2

3

4

Open Loop Root Locus

Real Axis

Imagin

ary

Axis

Thomas A6

-1 -0.5 0 0.5 1 1.5

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

0.1/T

0.2/T

0.3/T

0.4/T0.5/T0.6/T

0.7/T

0.8/T

0.9/T

/T

0.1/T

0.2/T

0.3/T

0.4/T0.5/T

0.6/T

0.7/T

0.8/T

0.9/T

/T

0.1

0.2

0.3

0.40.50.60.70.8

0.9

Open Loop Root Locus w ith Damping Ratio Lines

Real Axis

Imagin

ary

Axis

-40

-20

0

20

40

60

80

Magnitu

de (

dB

)

10-1

100

101

102

103

104

-225

-180

-135

-90

Phase (

deg)

Bode Diagram

Gm = 23.3 dB (at 1.16e+003 rad/sec) , Pm = 69.1 deg (at 157 rad/sec)

Frequency (rad/sec)

Thomas A7

******Closed Loop Response******

Transfer function:

3.213e-005 z^3 + 3.064e-005 z^2 - 3.198e-005 z - 3.049e-005

-----------------------------------------------------------

z^4 - 3.792 z^3 + 5.386 z^2 - 3.396 z + 0.8019

Sampling time: 8.3333e-005

Zero/pole/gain:

3.2127e-005 (z-0.9976) (z+1) (z+0.9515)

-------------------------------------------

(z-0.9973) (z-0.9801) (z-0.9617) (z-0.8531)

Sampling time: 8.3333e-005

0 100 200 300 400 500 600 700 800 900 10000

0.2

0.4

0.6

0.8

1

1.2

1.4

System: sys

Time (sec): 249

Amplitude: 1.06

Step Response

Samples (sec)

Am

plit

ude

**********END SIMULATION**********

Thomas B1

Appendix B: Project Completion Timeline

Week Goal Task Completed

1 January 27 Write tutorial introduction January 22

2 February 3 Verify motor parameters Not Completed

3 February 10

Simulate motor model in MATLAB February 10

Design/Simulate controller in MATLAB March 10

Design/Simulate controller in Simulink April 9

4 - 5 February 24 Make required adjustments to model and download to DS1103

March 12

6 March 3 Design/Build/Test hardware for motor subsystem February 12

7 March 10 Design/Build/Test hardware for optical encoder system February 17

8 - 10 March 31 Make required adjustments to controller model to work with motor and hardware and download to DS1103

March 12

11 - 13 April 21 Improve controller or Design/Build/Test additional controllers

April 23

14 April 28 Work on presentation/final report/tutorial May 12

15 May 5 Presentation May 5

16 May 11 Final Report Due May 12

Table B1: Schedule of Tasks and actual completion dates for this project for the Spring 2009 semester.

Thomas C1

Appendix C: Datasheet Excerpts

Transistor

Thomas C2

Inverter

Thomas C3

Thomas C4

Thomas C5

Thomas C6

Encoder

Thomas C7

Thomas C8

Thomas C9